Rerange - Emerson Rosemount 3051S Series Reference Manual

Configuration
October 2018
2.7.3

Rerange

The "Range Values" command sets each of the lower and upper range analog values (4 and 20
mA points) to a pressure. The lower range point represents 0 percent of range and the upper
range point represents 100 percent of range. In practice, the transmitter range values may be
changed as often as necessary to reflect changing process requirements. For a complete listing
of range and sensor limits, refer to the Specifications section of the Rosemount 3051S Series of
Instrumentation
Note
Transmitters are shipped from Emerson fully calibrated per request or by the factory default of
full scale (zero to upper range limit.)
Select from one of the methods below to rerange the transmitter. Each method is unique;
examine all options closely before deciding which method works best for your process.



Note
If the transmitter security jumper/switch is ON, adjustments to the zero and span cannot be
made. Refer to
Rerange with a Field Communicator or AMS Device Manager
only
The easiest and most popular way to rerange is to use the Field Communicator only. This
method changes the range values of the analog 4 and 20 mA points independently without a
pressure input. This means that when you change either the 4 or 20 mA setting, you also change
the span.
An example for the 4–20 mA HART output:
If the transmitter is ranged so that
4 mA = 0 inH
20 mA = 100 inH
and you change the 4 mA setting to 50 inH
are:
4 mA = 50 inH
20 mA = 100.
Note that the span was also changed from 100 inH
remained at 100 inH
To obtain reverse output, simply set the 4 mA point at a greater numerical value than the 20 mA
point. Using the above example, setting the 4 mA point at 100 inH
inH
26
Product Data
Rerange with a Field Communicator or AMS Device Manager only.
Rerange with a pressure input source and a Field Communicator or AMS Device Manager.
Rerange with a pressure input source and the local zero and span buttons (option D1).
"Wiring the device" on page 59
O, and
2
O,
2
O, and
2
O.
2
O will result in reverse output.
2
Sheet.
for security information.
O using the communicator only, the new settings
2
O to 50 inH
2
Reference Manual
00809-0100-801, Rev HA
O, while the 20 mA setpoint
2
O and the 20 mA point at 0
2
Configuration